1. Field of Invention
This invention relates to garage door assemblies and more specifically to assemblies for opening and closing garage doors having a horizontal axis of swinging.
2. Description of the Prior Art
In the case of conventional manually operated garage door assemblies, the person who is going to drive a vehicle into or out of the garage has to leave the vehicle to open the garage door on arrival and to close the same door when leaving. This disadvantage is particularly serious when the garage door is to be operated by handicapped persons or business vehicles.
Remote-controlled garage door assemblies are, of course, known but such assemblies usually depend upon power operation for lifting or lowering the door. Hence, the costs are so high that the use of such door assemblies is, in general, only reserved for special purposes.
However, door assemblies are known which can be remote-controlled without using a power supply. Such door assemblies have heretofore had to incorporate two springs, one acting as an energy storing member and the other compensating for a part of the weight of the door. This increases the cost of such door assemblies substantially compared with the conventional, manually operated door assemblies, as a number of additional parts are required in addition to a second spring.